Check out Dr. Gordon Giesbrecht a.k.a. Professor Popsicle. He's a professor at the University of Manitoba. He has spent his career studying cold water immersion survival.
He has a One - Ten - One rule:
Once in the water, you have ONE MINUTE to recover from the gasp reflex and control your breathing.
You have TEN MINUTES to make every attempt to get yourself out of the water before you lose the use of your extremities, your hands.
Once out, you have ONE HOUR to build a fire and literally wring all the water you can out of your clothes, before serious hypothermia sets in.
He has several videos available on Youtube.
Every Driver Training class is given this information. We also do a survival fire starting demo: cotton balls coated in vaseline and wrapped in foil and flint/steel sparker. Waterproof and works everytime.